A structure, such as a bridge, building or a tower, normally consists of multiple structural components. These structural components are connected typically by mechanical means to provide workability of the structure. In this disclosure, the connection between structural components (typically joints) or the structural components themselves are referred to as a part of the structure. A part of the structure may deteriorate with use of the structure over time, which degrades integrity of the structure and may cause economic loss or personal injuries. Therefore, the health condition of the structure is monitored constantly or regularly in many ways to avoid undesired loss or injuries.
Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the field relevant to the present disclosure as it existed before the priority date of each claim of this application.